Heart disease and its associated health issues are a large concern today. Mitral valve defects such as regurgitation are often caused by a dilation of the tissue surrounding the valve. This causes the mitral opening to enlarge, which prevents the valve leaflets from sealing properly. This heart condition is commonly treated by sewing a ridged ring around the valve. Cinching the tissue around the ring restores the valve opening to its approximate original size and operating efficiency.
The proper degree of cinching, however, is difficult to determine during open heart surgery. This is because the patient is under general anesthesia, in a prone position, with the chest wide open, and a large incision in the heart. These factors and others affect the ability to test the modified annulus for its therapeutic affect upon mitral valve leaflet coaptation. Even if the cinching is done well, the tissue may continue to change over the patient's lifetime such that the heart condition returns.